When doctors won't tell . . .
Of all the online nutritional information, nutritional facts, medical and
dietary sites there are to choose from, in an article entitled "How
to ease the pain" The Sunday Times magazine,
Culture, published a list of just five websites it
considered reliable and informative.This site was one of that five.

CONDITIONS
AND DISEASES PREVENTED AND HELPED BY A LOW-CARB, HIGH-FAT DIET

Sheehan's concern about the effects of
soy on cognitive function (detailed in his submission
to the FDA opposing the Protein Technologies Health Claim
Petition) is mainly based on the findings of Dr Lon White
from the Honolulu:Asia
Aging Study. Long-term data (30+ years)
from 7,000 men in a prospective epidemiological study in
Hawaii showed an association between consistently high levels
of tofu consumption in mid-life with low cognitive test
scores and (independently) with Alzheimer's disease in late
life. Persons who reported eating tofu at least twice
weekly had a 2.4 fold greater risk for development of Alzheimer's
disease compared with persons reporting little tofu consumption.

You can read more on how tofu
consumption results in accelerated brain aging, reduces cognitive
function and is associated with Alzheimer's disease at the Star
Bulletin which reports on Lon White's latest findings.

The hippocampus is the area of
the brain that is vital for learning and short-term memory.
Research by O'Dell
shows that genistein inhibits development of this brain function.

See also "Is
there a reason to believe Tofu may cause brain atrophy"
by Ian Williams Goddard and The
trouble with tofu: soy and the brain by John D MacArthur ( http://www.brain.com/cgi-bin/Brain.storefront/3c4382c3004dcff4271fc0a80a0c06a6/UserTemplate/26?id=13500&cat_id=37 )
This article is also found on the
Mercola website.

The high dose of genistein (20
mg/day) significantly increased lactate dehydrogenase (LDH)
in rat brain tissue homogenates, whereas the low dose of genistein
(2 mg/day) decreased LDH. In addition, DNA fragmentation was
detected in homogenates of brain tissue from rats receiving
either dose of genistein. These results are consistent with
those of in vitro studies indicating that high concentrations
of genistein caused cytotoxicity and DNA ladder formation in
primary cultures of cortical neurons.

These results suggest that chronic
administration of genistein at high doses may induce cytotoxicity
and apoptosis in the rat brain.

This double-blind randomized
trial does not support the hypothesis that the use of soy protein
supplement containing isoflavones improves cognitive function,
bone mineral density, or plasma lipids in healthy postmenopausal
women when started at the age of 60 years or later.

In the monkeys fed the higher
amount of isoflavones, frequencies of intense aggressive (67%
higher) and submissive (203% higher) behavior were elevated
relative to monkeys fed the control diet (P's < 0.05). In
addition, the proportion of time spent by these monkeys in physical
contact with other monkeys was reduced by 68%, time spent in
proximity to other monkeys was reduced 50%, and time spent alone
was increased 30% (P's < 0.02).

Using in situ hybridisation,
significant reductions were found in brain-derived neurotrophic
factor (BDNF) mRNA expression in the CA3 and CA4 region of the
hippocampus and in the cerebral cortex in the rats fed the diet
containing phytoestrogens, compared with those on the soya-free
diet.

Consistent with this hypothesis,
a reduction in BDNF mRNA expression has been observed in human
post-mortem Alzheimer's disease hippocampi.

We observed a reduction in the
intensity and number of BDNF-immunoreactive cell bodies within
both the Alzheimer's disease hippocampus and temporal cortex
when compared to normal tissue. These results support and extend
previous findings that BDNF mRNA is reduced in the human Alzheimer's
disease hippocampus and temporal cortex, and suggest that a
loss of BDNF may contribute to the progressive atrophy of neurons
in Alzheimer's disease.

Isoflavones form one of the main
classes of phytoestrogens and have been found to exert both
oestrogenic and anti-oestrogenic effects on the central nervous
system. The effects have not been limited to reproductive behaviour,
but include effects on learning and anxiety and actions on the
hypothalamo-pituitary axis. It is therefore possible that the
soya content of diet could have significant effects on brain
and behaviour and be an important source of between-laboratory
variability.

Compared with the rats fed the
iso-free diet, the rats fed the iso-150 diet spent significantly
less time in active social interaction and made a significantly
lower percentage of entries onto the open arms of the plus-maze,
indicating anxiogenic effects in both animal tests. The groups
did not differ in their basal corticosterone concentrations,
but the iso-150 group had significantly elevated stress-induced
corticosterone concentrations. Stress-induced plasma vasopressin
concentrations were also significantly elevated in the iso-150
diet group compared with the iso-free rats.

Major changes in behavioural
measures of anxiety and in stress hormones can result from the
soya isoflavone content of rat diet. These changes are as striking
as those seen following drug administration

These results indicate that consumption
of dietary phytoestrogens resulting in very high plasma isoflavone
levels (in many cases over a relatively short interval of consumption
in adulthood) can significantly alter sexually dimorphic brain
regions, anxiety, learning and memory. The findings of these
studies identify the biological actions of phytoestrogens, specifically
isoflavones and their metabolites, found in animal soy-containing
diets on brain and behavior and implicate the importance of
phytoestrogens given the recognized significance of estrogens
in brain and neural disorders, such as Alzheimer's disease,
especially in women.

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Barry Groves PhD, offering online nutritional facts and online
nutritional information. This website should be used to support rather
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